橘子味的心
标题:Spring EL bean引用实例

在Spring EL,可以使用点(.)符号嵌套属性参考一个bean。例如,“bean.property_name”。
public class Customer {
	
	@Value("#{addressBean.country}")
	private String country;
在上面的代码片段,它从“addressBean” bean注入了“country”属性到现在的“customer”类的“country”属性的值。

Spring EL以注解的形式

请参阅下面的例子,演示如何使用使用 SpEL 引用一个bean,bean属性也它的方法。
package com.yiibai.core;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

@Component("customerBean")
public class Customer {

	@Value("#{addressBean}")
	private Address address;

	@Value("#{addressBean.country}")
	private String country;
	
	@Value("#{addressBean.getFullAddress('yiibai')}")
	private String fullAddress;

	//getter and setter methods
	
	@Override
	public String toString() {
		return "Customer [address=" + address + "\n, country=" + country
				+ "\n, fullAddress=" + fullAddress + "]";
	}

}
package com.yiibai.core;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

@Component("addressBean")
public class Address {

	@Value("GaoDeng, QiongShang")
	private String street;

	@Value("571100")
	private int postcode;

	@Value("CN")
	private String country;

	public String getFullAddress(String prefix) {

		return prefix + " : " + street + " " + postcode + " " + country;
	}

	//getter and setter methods

	public void setCountry(String country) {
		this.country = country;
	}

	@Override
	public String toString() {
		return "Address [street=" + street + ", postcode=" + postcode
				+ ", country=" + country + "]";
	}

}

执行结果

Customer obj = (Customer) context.getBean("customerBean");
System.out.println(obj);

输出结果

Customer [address=Address [street=GaoDeng, QiongShang, postcode=571100, country=CN]
, country=CN
, fullAddress=yiibai : GaoDeng, QiongShang 571100 CN]


Spring EL以XML的形式

请参阅在XML文件定义bean的等效版本。
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans
	http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

	<bean id="customerBean" class="com.yiibai.core.Customer">
		<property name="address" value="#{addressBean}" />
		<property name="country" value="#{addressBean.country}" />
		<property name="fullAddress" value="#{addressBean.getFullAddress('yiibai')}" />
	</bean>

	<bean id="addressBean" class="com.yiibai.core.Address">
		<property name="street" value="GaoDeng, QiongShang" />
		<property name="postcode" value="571100" />
		<property name="country" value="CN" />
	</bean>

</beans>

目录

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